title: Highly selective ratiometric fluorescent probe for Au3+ and its application to bioimaging.
abstract: The 4-propargylamino-1,8-naphthalimide based fluorescent probe 1 has been explored as a sensor for selective detection of Au(3+). 4-Amino-1,8-naphthalimides, that possess typical intramolecular charge transfer (ICT) electronic characteristics, have been widely used as versatile platforms for fluorescent probes. The newly designed probe 1 contains a propargylamine moiety at C-4 of the naphthalimide chromophore that reacts with Au(3+) to generate a product that has distinctly different electronic properties from 1. Specifically, the probe undergoes a remarkable change in its absorption spectrum upon addition of Au(3+) that is associated with a distinct color change from yellow to light pink. In addition, a blue shift of ca. 56 nm also takes place in the emission spectra of the probe. Consequently, 1 serves as a reaction-based sensor or so called chemodosimeter for Au(3+). Importantly, surfactants enhance the rate of reaction of 1 with Au(3+), thus, enhancing its use as a real time sensor. Finally, the results of studies probing its application to bioimaging of Au(3+) in live cells show that the probe 1 has a unique ability to sense Au(3+) in cells and, in particular, in lipid droplets within cells.
authors.affiliation: Department of Chemistry and Nano Science and Department of Bioinspired Science (WCU), Ewha Womans University, Seoul 120-750, Republic of Korea.
authors.forename: Ji Young
authors.initials: JY
authors.lastname: Choi
authors.forename: Gun-Hee
authors.initials: GH
authors.lastname: Kim
authors.forename: Zhiqian
authors.initials: Z
authors.lastname: Guo
authors.forename: Hye Yeon
authors.initials: HY
authors.lastname: Lee
authors.forename: K M K
authors.initials: KM
authors.lastname: Swamy
authors.forename: Jaeyoung
authors.initials: J
authors.lastname: Pai
authors.forename: Seunghoon
authors.initials: S
authors.lastname: Shin
authors.forename: Injae
authors.initials: I
authors.lastname: Shin
authors.forename: Juyoung
authors.initials: J
authors.lastname: Yoon
mesh_terms: D015057:1-Naphthylamine / Q000031:analogs & derivatives* / Q000737:chemistry; D041721:3T3-L1 Cells; D017667:Adipocytes / Q000166:cytology; D000818:Animals; D015374:Biosensing Techniques / Q000379:methods; D002412:Cations / Q000032:analysis*; D005456:Fluorescent Dyes / Q000737:chemistry*; D006046:Gold / Q000032:analysis*; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D053644:Naphthalimides / Q000737:chemistry*; D061848:Optical Imaging / Q000379:methods*; D015363:Quinolones / Q000737:chemistry*
chemical_list: D002412:Cations; D005456:Fluorescent Dyes; D053644:Naphthalimides; D015363:Quinolones; C086538:4-amino-1,8-naphthalimide; D006046:Gold; D015057:1-Naphthylamine
keywords: Au(3+) sensing; Cell imaging; Fluorescent probe; Lipid droplet; Naphthalimide